For those doing holiday shopping, it is Cyber Monday, when companies follow their Black Friday deals with online steals. One of those hot online buys this holiday season is Katy Perry's latest hit album, "Prism."

(SOUNDBITE OF SONG)

KATY PERRY: (Singing) I used to bite my tongue and hold my breath. Scared to rock the boat and make a mess...

RENEE MONTAGNE, HOST:

Internationally, she has sold 5 million copies of her single "Roar."

(SOUNDBITE OF SONG)

PERRY: (Singing) I guess that I forgot I had a choice. I let you push me past the breaking point. I stood for nothing, so I fell for everything...

MONTAGNE: Critics have called the album inspirational, glistening, intimate.

INSKEEP: But officials in Australia gave it a different label: Biohazard. That's right. The album sleeve contains garden seeds.

MONTAGNE: Because of that, Australia's Department of Agriculture has deemed the album a potential danger to Australia's unique ecosystem. We asked science correspondent Dan Charles, who knows a lot about plants, to explain.

DAN CHARLES, BYLINE: I mean, it seems a little strange to say that little bits of seed wrapped into paper would be a threat. But it can be a threat. It can be a threat to the natural environment, and the natural vegetation of a place like Australia. And we have a term for this. We call them invasive species - you know, like actual invaders.

INSKEEP: Perry's production company says it had no intention of invading the Australian landscape. It says the seeds in the Australian version of the album are local. But it's the seeds coming through in the international mail that are worrying officials.

MONTAGNE: When people buy the CD online through sites like Amazon or eBay, the seeds could come from anywhere. We asked Dan Charles if this could be a problem in other places, too. He said yes, perhaps.

CHARLES: But I think the Australians are particularly sensitive to this because they've got a history of dealing with invasive species - whether those are animals or insects or plants. It's part of the history of that country. They've dealt with species that have come into the country and have really run wild, and it's been a big problem.

INSKEEP: OK, so what are Australians supposed to do if they find they've got foreign seeds in their possession? Don't panic. They're being told the government just asks that the seeds be disposed of carefully.